The wall spandrel element internal forces are similar to the frame element internal forces. They are:
P, the axial force
V2, the shear force in the 1-2 plane
V3, the shear force in the 1-3 plane
T, the axial torque
M2, the bending moment in the 1-3 plane (about the 2-axis)
M3, the bending moment in the 1-2 plane (about the 3-axis)
The positive directions of these forces are exactly the same as those described for the frame element.
Wall Spandrel Local Axes
The local 1-2 plane is in the plane of the wall spandrel. The positive local axis 1 is horizontal and has a positive projection on the global X-axis, or if the plane of the spandrel is oriented parallel to the global Y-Z plane, axis 1 is in the same direction as the positive global Y-axis. The positive local 1-axis points from the i-end of the spandrel to the j-end of the spandrel.
The positive local 2 axis points upward in the same direction as the positive global Z-axis.
The local 3 axis is horizontal and perpendicular to the plane of the spandrel. The direction of the positive local 3 axis is determined from the right-hand rule.
In the case where a wall spandrel is made up of a one or more beam-type frame element, the local axes of the spandrel are still the same as those described above. The local axes orientation of a spandrel are independent of the local axes orientation of its component area and line objects.
Pier Element Internal Forces
Output Convention - Frame Element Internal Forces